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-rw-r--r--libtommath/bn_mp_invmod.c50
1 files changed, 15 insertions, 35 deletions
diff --git a/libtommath/bn_mp_invmod.c b/libtommath/bn_mp_invmod.c
index 36011d0..7b35a24 100644
--- a/libtommath/bn_mp_invmod.c
+++ b/libtommath/bn_mp_invmod.c
@@ -1,43 +1,23 @@
-#include <tommath_private.h>
+#include "tommath_private.h"
#ifdef BN_MP_INVMOD_C
-/* LibTomMath, multiple-precision integer library -- Tom St Denis
- *
- * LibTomMath is a library that provides multiple-precision
- * integer arithmetic as well as number theoretic functionality.
- *
- * The library was designed directly after the MPI library by
- * Michael Fromberger but has been written from scratch with
- * additional optimizations in place.
- *
- * The library is free for all purposes without any express
- * guarantee it works.
- *
- * Tom St Denis, tstdenis82@gmail.com, http://libtom.org
- */
+/* LibTomMath, multiple-precision integer library -- Tom St Denis */
+/* SPDX-License-Identifier: Unlicense */
/* hac 14.61, pp608 */
-int mp_invmod (mp_int * a, mp_int * b, mp_int * c)
+mp_err mp_invmod(const mp_int *a, const mp_int *b, mp_int *c)
{
- /* b cannot be negative */
- if ((b->sign == MP_NEG) || (mp_iszero(b) == MP_YES)) {
- return MP_VAL;
- }
+ /* b cannot be negative and has to be >1 */
+ if ((b->sign == MP_NEG) || (mp_cmp_d(b, 1uL) != MP_GT)) {
+ return MP_VAL;
+ }
-#ifdef BN_FAST_MP_INVMOD_C
- /* if the modulus is odd we can use a faster routine instead */
- if ((mp_isodd(b) == MP_YES) && (mp_cmp_d(b, 1) != MP_EQ)) {
- return fast_mp_invmod (a, b, c);
- }
-#endif
+ /* if the modulus is odd we can use a faster routine instead */
+ if (MP_HAS(S_MP_INVMOD_FAST) && MP_IS_ODD(b)) {
+ return s_mp_invmod_fast(a, b, c);
+ }
-#ifdef BN_MP_INVMOD_SLOW_C
- return mp_invmod_slow(a, b, c);
-#else
- return MP_VAL;
-#endif
+ return MP_HAS(S_MP_INVMOD_SLOW)
+ ? s_mp_invmod_slow(a, b, c)
+ : MP_VAL;
}
#endif
-
-/* ref: $Format:%D$ */
-/* git commit: $Format:%H$ */
-/* commit time: $Format:%ai$ */